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JC McBee
01-30-2006, 07:14 PM
Hi, I have a pond,that i need to draw waterfrom,to water my front and back yard. i need help , should i use a sub/pump? if so what size,gpm can i use to make this work. can i use valves/hose bib or will restriction hurt the pump ? thank you for any help and all help. jc mcbee

Bob NH
02-01-2006, 01:27 PM
I would not use a submersible. They provide too much pressure, need special handling, and cost more than the alternatives.

Any good system design starts with requirements. Estimate how many gallons per minute you want, and the pressure you need for your watering and there are several pumps available.

You might want to start with area to be watered. If you have an area of 100 ft x 100 ft and want to add 1/2 inch of water in 2 hours, you will need:

100 x 100 x (0.5"/12"/ft) x 7.48 gallons per cu ft /120 minutes = 26 gallons per minute.

You can plug in your own numbers to detemine what you need.

A 1 HP Goulds GT10 will give you 29 GPM at 40 psi with 5 ft of suction lift from the pond. It will give deliver 18 GPM at 45 psi if you throttle it down. It is listed at $360 in the Grainger catalog. Smaller pumps are available and you could shop on line for price and quality.

The choices are shallow well jet, or centrifugals that will give you a lot more flow and a little less pressure. You will find that pure centrifugals are more efficient than jet pumps, but if you want lower flow, such as 15 GPM at 40 psi or more, you will have to go with a jet pump or a multistage pump.

If you can set up your irrigation setup so it is more or less constant flow you can avoid the expense of a pressure tank.

speedbump
02-21-2006, 11:56 AM
Do you want to use this strictly for sprinklers or do you want to wash the dog, car, hand water etc. If you want to do the above a tank will necessary along with a pressure switch. With this you don't want a centrifugal pump.

I like a submersible as long as you buy the right one for the job.

First thing though is lay it out like Bob says. For it to work properly there is a lot to do before setting the pump.

bob...